The present invention relates generally to electric motors for automobile engine cooling applications and, more particularly, to the integrated speed control of a dual motor configuration having a primary brushless motor and a secondary brush motor.
In automotive applications, including engine cooling applications, there is a need for dual motor configurations. One example is the use of dual engine cooling fans powered by dual motors. Conventionally, this has been achieved using dual brush motors. Wound field-type motors generally have speed controlled by altering the field flux. This is done by changing the current or the number of coil turns in the field winding. With these types of motors, however, the number of speeds available is limited.
Accordingly, there is a need to provide a dual motor configuration for an engine cooling application whereby different combinations of speeds across and throughout a range of speeds of first and second motors can be selectively and continuously chosen to meet cooling requirements of an engine.